027 The Mysteries of the Rose Cross has been my favorite lecture series from the Rosenkreutz Institute ever! This lecture series has personally influenced me in so many ways. This, as well as 026 Michael the Archangel and the Shadow of the Spirit lecture series, are the two foundational lecture series that I would recommend for all students of the spirit here at the Rosenkreutz Institute. If you ever had any questions about the significance of the Rose Cross Meditation, the Holy Grail and other spiritual practices to help advance the student upon one's path (e.g., how to purify the air around one's self) then this lecture series is something I would highly recommend. I would recommend students take the 026 lecture series before taking 027 lecture series. This is because what one is taught in 026 is later expanded up and brought to further clarity in the 027 lecture series. With that being said, 027 The Mysteries of the Rose Cross and 026 Michael the Archangel and the Shadow of the Spirit are I think two of the most important lectures that any modern student of the spirit could listen to. Please, by all means, take these two classes!!!